Implications of Wintertime Blocking Episodes over Ural-Siberia for the Regional Climate in Southeast Asia

Two major wavetrain patterns are identified in the Eurasian continent by Empirical Orthogonal Function (EOF) analysis, which are classified as Ural-type and Siberia-type. In general, the Ural-type wavetrain has dominant periodicities at 7-9 days and 16-20 days while the Siberia-type has a dominant one at 6-10 days. On the weekly cycle, the wavetrain might exert strong influence on the cold surge events, which pathway may be related to the wavetrain type. On the other hand, these patterns show decadal variations, which might relate to the signal originating from the North Atlantic Ocean.